Configuring WINS Database Replication
from Chapter 18, Microsoft Windows 2000 Administrator's Pocket Consultant by William R. Stanek.
You can configure WINS servers to replicate their databases with each other. This ensures that each server's database is current and reflects changes on the network. As an administrator, you have many options for controlling when replication occurs. You can also force replication at any time.
Replication is handled with push partners and pull partners. A push partner is a WINS server that notifies other WINS servers of changes on the network. A pull partner is a WINS server that requests replicas from a push partner. You can configure any WINS server as a push partner or pull partner, or both.
To increase the reliability of replication, you can configure persistent connections between replication partners. With persistent connections, replication partners keep connections open even when they're idle. This allows the WINS servers to replicate changes throughout the network quickly and efficiently.
Setting Default Replication Parameters
Before you create replication partners, you'll want to set default parameters. These parameters are used to configure new push and pull partners.
Assigning General Parameters
General parameters control replication and migration. You can set general parameters by completing the following steps:
Expand the view for the server you want to work with in the WINS console.
Right-click Replication Partners in the tree view, and then choose Properties.
In the General tab, select or clear Replicate Only With Partners. If it's selected, this option ensures that WINS information is only replicated with designated replication partners. If it's cleared, you can manually replicate WINS information with any WINS server on the network.
Static mappings are created for non-WINS clients on the network, which allows their computer names to be registered in WINS. If multiple computers may use the same IP addresses, you may want WINS to overwrite existing entries with information from new registrations. To do this, select Overwrite Unique Static Mappings At This Server. Click OK.
Assigning Default Push Replication Parameters
By default, replication partners are configured to use both push and pull replication. In this scenario, you usually don't want push replication to occur automatically and instead rely primarily on pull replication for automatic updates. Additionally, because partners are configured for both push and pull replication, you can still initiate push replication manually if need be.
If you want push replication to occur automatically or you want to change the default settings, follow these steps:
Expand the view for the server you want to work with in the WINS console.
Right-click Replication Partners in the tree view, and then choose Properties.
Click the Push Replication tab, shown in Figure 18-5.
Figure 18-5: Assign default parameters to manage push replication in the enterprise.
Push replication can be initiated when WINS starts and when address changes occur. By default, these options aren't selected. To change this behavior, select At Service Startup or When Address Changes or both.
Number Of Changes In Version ID Before Replication specifies the number of registrations and changes that must take place before pull partners are notified, which triggers database replication. This counter is for local changes only and doesn't tally changes pulled from other partners. If the field is set to zero, no push replication takes place.
By default, push replication partners use persistent connections. If you don't want to use persistent connections, clear the Use Persistent Connections For Push Replication Partners check box. Click OK.
Assigning Default Pull Replication Parameters
Pull replication is the default replication technique for replication partners. Because of this, most of the default pull replication parameters are enabled automati cally. If you'd rather use push replication as the primary replication technique, you should enable automatic push replication using the options of the Push Replication tab and then disable pull replication defaults using the Pull Replication tab.
To change pull replication settings, follow these steps:
Expand the view for the server you want to work with in the WINS console.
Right-click Replication Partners in the tree view, and then choose Properties.
Click the Pull Replication tab, shown in Figure 18-6.
Figure 18-6: Pull replication is the primary replication technique you should use.
Start Time sets the hour in the day when replication should begin. The time is set using a 24-hour clock.
Replication Interval sets the intervals at which scheduled replication should occur, such as every 30 minutes.
Number Of Retries sets the number of times the WINS server will retry a connection to a pull partner in the event of a failed connection.
By default, pull replication starts when the WINS server starts. To change this behavior, clear the Start Pull Replication At Service Startup check box. When it's cleared, pull replication starts only at the specified Start Time.
By default, push replication partners use persistent connections. If you don't want to use persistent connections, clear the Use Persistent Connections For Pull Replication Partners check box. Click OK.
Creating Push and Pull Partners
Push and pull partners are needed to replicate WINS databases whenever there are multiple WINS servers on a network. Replication partners get their initial settings from the default replication parameters you've configured for a server. You must configure replication separately for each WINS server on the network.
To designate WINS servers as push and pull partners, follow these steps:
Expand the entry for the server you want to work with in the WINS console. This server is the one for which you'll configure replication partners.
Right-click Replication Partners in the console tree, and then select New Replication Partner.
Type the name or IP address of the replication partner. Or click Browse to search for a computer to work with in the Select Computer dialog box.
Click OK. If the server can be contacted, the replication entry is created automatically using the default settings. The server is configured as a push and pull replication partner.
Changing Replication Type and Settings for Partners
Default settings are used to initialize the parameters for replication partners. You can change these parameters on a per partner basis at any time by completing the following steps:
Expand the entry for the server you want to work with in the WINS console. This server is the one for which you'll configure replication partners.
In the console tree, select Replication Partners. This displays current replication partners for the server in the right pane.
Right-click the replication partner you want to work with, and then select Properties.
Click the Advanced tab, shown in Figure 18-7.
The Replication Partner Type selection list shows what type of replication is configured for the partner. By default, most clients are set to use both push and pull replication. You can change this behavior by selecting the Push option or the Pull option.
The remaining settings are the same as those discussed previously in the sections of this chapter entitled "Assigning Default Push Replication Parameters" and "Assigning Default Pull Replication Parameters." Note that you can only configure some of the options through the Replication Partners Properties dialog box.
Click OK when you're finished.
Triggering Database Replication
Sometimes you may want to immediately update the WINS databases on replication partners. You can do this by forcing immediate database replication with partners or by triggering replication among partners. You can also specify the type of replication to initiate.
Forcing replication with all partners To force replication with all partners, right-click the Replication Partners folder for the server whose database you want to replicate, and then select Replicate Now.
Triggering push replication with all partners To start push replication with all partners, right-click the server whose database you want to replicate, and then select Start Push Replication.
Triggering pull replication with all partners To start pull replication with all partners, right-click the server whose database you want to replicate, and then select Start Pull Replication.
Triggering push or pull replication with an individual partner To start push or pull replication with an individual partner, follow these steps:
In the WINS console, click the Replication Partners folder for the server whose database you want to replicate. Currently configured partners are displayed in the right pane.
Right-click the partner with which you want to replicate the database, and then select Start Push Replication or Start Pull Replication, as appropriate.
Figure 18-7: You can change the default replication settings for each replication partner, if necessary.
Managing the WINS Database
You should actively manage the WINS database to maintain the health of WINS name resolution on the network. The sections that follow examine common management tasks.
Examining WINS Database Mappings
When the Active Registrations folder is selected in the console tree, the right pane of the WINS console displays the records that you've selected for viewing. Each entry represents a record in the WINS databases. At the left side of the entry, you'll see one of two icons. An icon of a single computer shows that the mapping is for a unique name. An icon with multiple computers shows that the mapping is for a group, domain, Internet group, or multihomed entry. Mappings also show the following:
Record Name The complete NetBIOS name of the computer, group, or service registered in the database.
Type The record type associated with this mapping, such as 00h WorkStation.
IP Address The IP address associated with the mapping.
State The state of the record, such as active or released.
Static An X in this column indicates a static mapping.
Owner The IP address of the WINS server that owns the record.
Version The database version ID from which the record originates.
Expiration The time and date the mapping expires. Static mappings have an expiration date of Infinite, which means they don't expire (unless they are overwritten or deleted).
Cleaning and Scavenging the WINS Database
You should periodically clean the WINS database to ensure that old computer names are removed. The process of cleaning the database, called scavenging, is initiated automatically according to the relationship between the Extinction Interval and the Extinction Timeout set in the Server Properties dialog box.
You can also initiate scavenging manually. To do this, select the server you want to work with in the WINS console, and then, from the Action menu, choose Scavenge Database.
Verifying the Consistency of the WINS Database
On a large network with multiple WINS servers, the databases on different servers can sometimes get out of sync with each other. To help maintain the integrity of the databases, you may want to verify their consistency periodically. You can perform two types of consistency checking: database consistency and version ID consistency.
When you verify database consistency, WINS checks the integrity of database records on WINS servers. To verify database consistency, select the server you want to work with in the WINS console and then, from the Action menu, choose Verify Database Consistency.
When you verify version ID consistency, WINS checks the local records with records on other WINS servers to ensure that the correct record versions are being maintained. To verify version ID consistency, select the server you want to work with in the WINS console and then, from the Action menu, choose Verify Version ID Consistency.
To configure automatic database consistency checks, complete the following steps:
Right-click the server you want to work with in the WINS console, and then select Properties.
On the Database Verification tab, select Verify Database Consistency Every _, as shown in Figure 18-8. Then in the field provided, type a time interval for the checks, such as every 24 hours or every 48 hours.
In the Begin Verifying At field, enter the time when you want verification to start. You set the time with a 24-hour clock.
As necessary, set the Maximum Number Of Records Verified Each Period. The default value is 30,000.
Figure 18-8: Rather than manually verifying data, you can configure automatic consistency checks.
Best Practice Don't forget that consistency checks can use considerable system and network resources. To gain better control over when checks occur, you'll usually want to check the WINS database in 24-hour increments, and then use the Begin Verifying At fields to set a time that occurs after hours. For example, if you set the database checks on a 24-hour cycle, then enter a begin time of 2 hours, 0 minutes, and 0 seconds, WINS will verify the database at 2 a.m. every 24 hours.
You can verify records against servers designated as owners or against randomly selected partners. Random selection works best if you have a very large network and can't check all the records at any one time. Otherwise, select Owner Servers to verify records on the servers designated as record owners.
Click OK when you're finished.
Backing Up and Restoring the WINS Database
Two WINS server tasks that administrators often overlook are backup and restore.
Configuring WINS for Automatic Backups
The WINS database isn't backed up by default. If you have problems with the database you won't be able to recover it. To protect against database failure, you should configure automatic backups or run manual backups periodically. To prepare WINS to perform automatic backups, follow these steps:
Right-click the server you want to work with in the WINS console, and then select Properties.
In the General tab, enter the folder path that you want to use for backups in Default Backup Path. Click Browse if you want to search for a folder.
To ensure that backups are created whenever the WINS server is stopped, select Backup Database During Server Shutdown.
Click OK. Automatic backups will then be performed every three hours.
Restoring the Database
If you have a good backup of the WINS database, you can restore it by completing the following steps:
Select the server you want to work with in the WINS console.
Click the Action menu, choose All Tasks, and then select Stop.
Click the Action menu, and then select Restore Database.
In the Browse For Folder dialog box, select the wins_bak subdirectory containing the most recent backup and then click OK.
If the restore is successful, the WINS database is restored to its state at the time of the backup. Click the Action menu, choose All Tasks, and then select Start.
If the restore is unsuccessful, you may need to clear out all WINS files and then start with a fresh database.
Clearing Out WINS and Starting with a Fresh Database
If WINS won't restore using a backup or won't start normally, you may need to clear out all WINS records and logs and then start with a fresh database. To do this, follow steps:
Right-click the server you want to work with in the WINS console, and then select Properties.
On the Advanced tab, note the folder path set in Database Path, and then click OK to close the Properties dialog box.
Stop the server by clicking the Action menu, choosing All Tasks, and then selecting Stop.
Using Microsoft Windows Explorer, delete all files in the WINS database folder.
In the WINS console, right-click the server you're recovering, choose All Tasks, and then select Start. This starts the WINS servers.
from Microsoft Windows 2000 Administrator's Pocket Consultant by William R. Stanek. Copyright © 1999 Microsoft Corporation.